What type of architecture my project is?

Question

Hi In some post i have seen the below things Tier represents different hardware box. Means the components are physically separated to different machines. But in case of layer all component remains in same system. In Visual studio 2013 i developed a project. In solution project i took 3 projects one is web application project for Presentation logic and 2nd one is class library project for Business layer logic and the 3rd one is also class library for Data access layer logic. Here 3 layers are seperated in a solution project in the same system. So i confused weather is a 3-tier architecture or a 3-layer architecture. Please let me know which type of architecture it was..

Pranay Rana · Answer

Concept wise Tier - its term related to physical structure. that means 1 tier means one machine. so 3 Tier means three machines running three different part of application. Layer - its term related to logical structure of application. if you create 3 layer means three logical part of application. And if you put this 3 layer in to three different machine than it becomes 3 Tier. So do not mix up the terms. I understood this concept from Martin flower book Enterprise Application Architecture.